GB683940A - Improvements in and relating to cathodes for electric discharge apparatus - Google Patents

Improvements in and relating to cathodes for electric discharge apparatus

Info

Publication number
GB683940A
GB683940A GB17063/51A GB1706351A GB683940A GB 683940 A GB683940 A GB 683940A GB 17063/51 A GB17063/51 A GB 17063/51A GB 1706351 A GB1706351 A GB 1706351A GB 683940 A GB683940 A GB 683940A
Authority
GB
United Kingdom
Prior art keywords
boride
core
heating
metal
wire
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB17063/51A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
British Thomson Houston Co Ltd
Original Assignee
British Thomson Houston Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by British Thomson Houston Co Ltd filed Critical British Thomson Houston Co Ltd
Publication of GB683940A publication Critical patent/GB683940A/en
Expired legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J1/00Details of electrodes, of magnetic control means, of screens, or of the mounting or spacing thereof, common to two or more basic types of discharge tubes or lamps
    • H01J1/02Main electrodes
    • H01J1/13Solid thermionic cathodes
    • H01J1/14Solid thermionic cathodes characterised by the material
    • H01J1/148Solid thermionic cathodes characterised by the material with compounds having metallic conductive properties, e.g. lanthanum boride, as an emissive material
    • CCHEMISTRY; METALLURGY
    • C25ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; APPARATUS THEREFOR
    • C25CPROCESSES FOR THE ELECTROLYTIC PRODUCTION, RECOVERY OR REFINING OF METALS; APPARATUS THEREFOR
    • C25C7/00Constructional parts, or assemblies thereof, of cells; Servicing or operating of cells
    • C25C7/02Electrodes; Connections thereof
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J17/00Gas-filled discharge tubes with solid cathode
    • H01J17/02Details
    • H01J17/04Electrodes; Screens
    • H01J17/06Cathodes
    • H01J17/066Cold cathodes
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01JELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
    • H01J2893/00Discharge tubes and lamps
    • H01J2893/0064Tubes with cold main electrodes (including cold cathodes)
    • H01J2893/0065Electrode systems
    • H01J2893/0066Construction, material, support, protection and temperature regulation of electrodes; Electrode cups

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Solid Thermionic Cathode (AREA)

Abstract

683,940. Cathode materials and processing; thermionic valves. BRITISH THOMSONHOUSTON CO., Ltd. July 18, 1951 [Aug. 8, 1950], No. 17063/51. Class 39(i) A cathode comprises an emitting coating of a metal boride supported by a carbon or by an intermediate layer of the carbide, nitride or boride of a refractory metal which forms the core. Borides of rare earth metal, including misch metal, alkaline earth metal, thorium and uranium may be used as described in Specification 678,258 and the core may be of tungsten, molybdenum, platinum, columbium or tantalum wire 0.02 ins. diameter overwound with wire of 0.01 ins. diameter. The tantalum may be carbonized by heating for 1 min. at 2300‹C in powdered sugar charcoal to give a carbide layer 2 mils. thick and the spaces between the wire turns may be packed with lanthanum boride or the boronizing may be produced by heating in powdered boron. The nitride may be produced by heating the core in nitrogen or ammonia to 2000-2500‹C. A valve having anode 7, screen grid 8 and control grid 9 has a cathode consisting of a graphite rimmed disc 10 filled with boride 12 and heated by radiation and electron bombardment from a coil 13.
GB17063/51A 1950-03-31 1951-07-18 Improvements in and relating to cathodes for electric discharge apparatus Expired GB683940A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US153212A US2639399A (en) 1950-03-31 1950-03-31 Electron emitter

Publications (1)

Publication Number Publication Date
GB683940A true GB683940A (en) 1952-12-10

Family

ID=22546234

Family Applications (2)

Application Number Title Priority Date Filing Date
GB5910/51A Expired GB678258A (en) 1950-03-31 1951-03-12 Improvements in and relating to electron emitters
GB17063/51A Expired GB683940A (en) 1950-03-31 1951-07-18 Improvements in and relating to cathodes for electric discharge apparatus

Family Applications Before (1)

Application Number Title Priority Date Filing Date
GB5910/51A Expired GB678258A (en) 1950-03-31 1951-03-12 Improvements in and relating to electron emitters

Country Status (6)

Country Link
US (1) US2639399A (en)
BE (1) BE502232A (en)
CH (1) CH301197A (en)
DE (1) DE856666C (en)
GB (2) GB678258A (en)
NL (1) NL80503C (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0013201B1 (en) * 1978-12-27 1982-05-19 Thomson-Csf Directly heated cathode and high frequency electron tube comprising such a cathode

Families Citing this family (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2744073A (en) * 1952-11-22 1956-05-01 Battelle Development Corp Thermionic emitter materials
DE971413C (en) * 1953-10-02 1959-01-22 Siemens Ag Device for crucible zone melting
US3312856A (en) * 1963-03-26 1967-04-04 Gen Electric Rhenium supported metallic boride cathode emitters
US3505553A (en) * 1966-05-12 1970-04-07 Philips Corp Radio-interference-free low-pressure mercury-vapor lamp
US3440475A (en) * 1967-04-11 1969-04-22 Lokomotivbau Elektrotech Lanthanum hexaboride cathode system for an electron beam generator
US3944866A (en) * 1974-04-08 1976-03-16 Canadian Patents & Development Ltd. Thermionic emitter of lanthanum strontium vanadates
JPS5451776A (en) * 1977-10-03 1979-04-23 Nippon Hoso Kyokai <Nhk> Gas discharge display panel
US4260525A (en) * 1978-11-27 1981-04-07 Rca Corporation Single-crystal hexaborides and method of preparation
DE4305558A1 (en) * 1993-02-24 1994-08-25 Asea Brown Boveri Process for the manufacture of wires which are especially suitable for cathodes of electron tubes
US6025038A (en) * 1998-08-26 2000-02-15 Board Of Regents Of The University Of Nebraska Method for depositing rare-earth boride onto a substrate
US6077617A (en) * 1998-08-26 2000-06-20 Board Of Regents Of The University Of Nebraska Rare-earth boride thin film system
US8501136B2 (en) * 2006-02-06 2013-08-06 The University Of North Carolina At Chapel Hill Synthesis and processing of rare-earth boride nanowires as electron emitters
DE102011013262A1 (en) 2011-03-07 2012-09-13 Adlantis Dortmund Gmbh Electron-ionization source has photoelectrons that are generated from atmospheric-stable layer by ultra-violet source and are actuated with distance of acceleration in dimension of average free path length of gas

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1023485A (en) * 1908-11-20 1912-04-16 Orlando M Thowless Illuminant for electrical incandescent lamps.
US2117636A (en) * 1934-03-24 1938-05-17 Gerald B Tjoflat Thermionic electrode
US2501089A (en) * 1945-11-29 1950-03-21 Martin A Pomerantz Thermionic electron emitter
US2502331A (en) * 1948-12-21 1950-03-28 Rca Corp Geiger-muller counter for radioactive emission

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0013201B1 (en) * 1978-12-27 1982-05-19 Thomson-Csf Directly heated cathode and high frequency electron tube comprising such a cathode

Also Published As

Publication number Publication date
BE502232A (en)
US2639399A (en) 1953-05-19
DE856666C (en) 1952-11-24
GB678258A (en) 1952-08-27
NL80503C (en)
CH301197A (en) 1954-08-31

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